Doorbell and porch light control



Jan. 16, 1962 c. J. BISHOFBERGER 3,

DOORBELL AND PORCH LIGHT CONTROL Filed March 12, 1956 35 J10 J 33 M us we 60 INVENTOR.

CARL J. BISHOFBERGER ATTORNEY United States Patent 3,017,623 DOORBELL AND PORCH LIGHT CONTROL Carl J. Bishofberger, Minneapolis, Mirna, assiguor to Minneapolis-Honeywell Regulator Company, Minneapolis, Minn., a corporation of Delaware Filed Mar. 12, 1956, Ser. No. 571,056 4 Claims. (Cl. 340322) The novel circuitry disclosed relates to an improved arrangement of a porch light and doorbell for household use.

In most residences there are provided two independent circuits for the front porch light and the doorbell. After dark, the usual procedure upon noting the ringing of the doorbell is for the occupant of the house to switch his front porch light on to determine the identity of his guest. Many times the occupant of the house, after admitting the guest,forgets to switch off the front porch light and the light is allowed to burn uselessly for long periods of time. This same carelessness may extend even to the extent of neglecting to turn the light on at the time of opening the door and results in an impolite or even sometimes dangerous act. The novel circuitry proposed would overcome these defects as well as provide utility which could be utilized by the home owner under circumstances other than the admission of a guest to his home, as will be noted below.

The novel circuitry disclosed consists of an improved combination ofa doorbell and porch light, wherein, upon energizing the doorbell switch the front porch light is automatically turned on. A relay utilizing interconnecting and interlocking contacts maintains the porch light in an energized state after the doorbell switch has been deenergized and the energization of the relay is then controlled by a bimetal switch. The bimetal switch provides a time delay and allows the light to be left on for a predetermined period after the deenergization of the doorbell switch. This arrangement provides for the polite and immediate illumination of the front porch upon energization of the doorbell and yields automatic protection against overlooking the fact that the porch light has been left on. With this arrangement theporch light is automatically turned off after the predetermined time delay and requires no further attention from the householder. v

This circuitry not only can be used by the occupant of the house in connection with answering the doorbell, but allows him to utilize his own' doorbell and porch light for safety and convenience. It will be noted that by energizing his own doorbell upon leaving his home, the householder has a light which will guide his way down his front stairs and walk, and which will be automatically extinguished by the bimetal operated switch. This same operation can be utilized upon arriving home in the dark, and thereby affords protection and necessary light to conveniently open the door.

It is an object of this invention to provide an improved circuit which operates two normally independent circuits simultaneously and retains one in operation for a fixed period, but allows the other to be deenergized at once.

It is a further object of this invention to provide an economical and improved circuit for operating a house porch light and doorbell from the doorbell switch, and which retains the energization of the light for a fixed time delay after the bell has been rung.

Still a further object of this invention is to provide an improved circuit which can be made economically for a house porch light and which adds safety and convenience without adding switches which would not normally be installed.

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These and other objects will become apparent when the single circuit diagram disclosed is considered with the following description of its operation.

In the novel circuitry disclosed there are two power lines 10 and 11 and which would normally be energized by 115 'volts A.C. at cycles. Connected to lines 10 and 11 by leads 12 and 13 is the primary winding 14 of transformer 15. The transformer 15 is of a stepdown type normally used in bell ringing and low voltage con trol circuits. The transformer 15 further has a secondary winding 16. One extremity 17 of the secondary winding 16 is connected by leads 18 and 20 to an audible signal control winding 21, which may be a doorbell, doorchime, or similar device. Winding 21 is then connected by lead 22 to one terminal 23 of a momentary push button switch generally shown at 24. The switch 24 further contains a push button operating member 25 and a second terminal 26. The terminal 26 is connected by a conductor 28 to a terminal 32 on the secondary winding 16 of transformer 15. It will be noted that the combination of the transformer secondary winding 16, operator 21, and switch 24 constitute a conventional doorbell circuit.

An additional audible signal control means can be added to transformer secondary winding 16 without disturbing the previously described circuitry. As an example of this, a circuity consisting of conductors 18 and 3-3, audible signal means '34, push button 35, and leads 36 and 28 by have been disclosed. It is obvious that upon operation of push button switch 35 that the audible signal means 34 is energized and that its operation is completely independent of the remainder of the circuitry. This added circuit could represent a back or side door signal and is illustrative only.

A bimetal operated switch is generally shown at 40 and includes a bimetal member 41 rigidly mounted at 42 and having a contact 43 at the end remote from its rigid mounting. The contact 43 cooperates with a second contact 44 which in turn is rigidly mounted at 45. Connected between terminal 17 of the transformer secondary winding 16 and contact 43 is a heater 46 which is in a heat transferring relation with the bimetal 41. The contact 44 is in turn connected by lead 47 to a relay generally shown at 50. Relay 50 includes three simultaneously movable contacts 51, 52 and 53 as well as three fixed contacts 54, 55 and 56. Movable contacts 5 1 and 52 are joined together electrically by lead 57 and then in turn by a lead 58 are connected to the relay 50. Fixed contact 55 is connected to terminal 23 of switch. 24 by lead 60 and fixedcontact 54 is connected by lead 61 to lead 28.

Contacts 53 and 56 form a control circuit through leads 62 and 63 across a switch generally disclosed at 64. The switch 64 corresponds to the normal interior porch light switch and is connected in series with a light 65 across power leads 10 and 11 by means of conductors 66 and 67 in a manner well known in the art.

The operation of this circuit can best be understood by considering it initially as completely deenergized, as shown. By operating switch 64 it is obvious that light 65 can be manually controlled on or off. It is further noted that the operation of either switch 24 or 35 will operate its respective audible signal means 21 or 34. With the novel arrangement disclosed, the light 65, push button 24, and a front porch door (not shown) would all be located in the same vicinity so that the light from 65 would be available to illuminate a person standing at the door. This would correspond with the main entrance to a conventional house.

The operation of push button 24, in the improved circuitry disclosed, causes the operation of the audible signal means 21 and also supplies power from terminal 32 of the secondary winding 16 through conductor 28, the push button member 25, lead 60, contacts 55 and 52, lead 58, relay 50, contacts 43 and 44, and heater 46 to energize the relay 50. It is understood that the contacts 52 and 55 remain closed upon the operation of relay 50 until contacts 51 and 54 have closed. With this overlapping contact arrangement the energization of the relay is maintained through contacts 51 and 54 after the circuit through contacts 52 and 55 have been broken. The operation of relay 50 in turn causes relay contacts 53 and 56 to close thereby shorting switch 64. The shorting of switch 64 operates the light 65 and the light is retained on even if the switch 24 is released. The audible signal means 21 is not disabled by the disclosed circuitry nor is it rung continuously. It remains completely under control of the doorbell button 24.

It has been noted that after relay 50 has been energized, that a holding circuit is made through its contacts 51 and 54 and through heater 46. The heat from heater 46 is transmitted to the bimetal 41 and causes the bimetal to warp in the upward direction, as noted by an arrow. As soon as the bimetal 41 has warped a sufficient distance to open contacts 43 and 44, the circuit to relay Stl is opened and the contacts are returned to the position shown in the disclosed circuit. The length of time which is taken for the bimetal 41 to warp sufficiently to open contacts 43 and 44 can either be set permanently or be made adjustable by means well known in the art.

With the circuit disclosed it is obvious that it would be possible to control any number of lights and audible signal means or doorbells in a household or other location.

The audible signal means disclosed in this application could easily be a doorbell, doorchime, or other door signal means including lights or control circuits. Since the principles disclosed in this application could be applied to numerous devices and locations the applicant wishes to be restricted only in the scope of the appended claims, as the preferred embodiment disclosed would suggest many applications to those skilled in the art.

I claim as my invention:

1. A household electric circuit comprising: a source of power, circuit means including a porch light and first switch means connected to said source of power, an audible doorbell signal, low voltage coupling means, second circuit means including said low voltage coupling means, said doorbell signal and a momentary type low voltage switch connected to momentarily energize said doorbell signal and concurrently with operation of said momentary switch, a bimetal operated switch, relay means including said first switch means and a second switch means, third circuit means connecting said coupling means to said relay means through said second switch means and said momentary type low voltage switch and including a heater associated with said bimetal, said third circuit means providing an arrangement for simultaneous energization of said porch light and said signal upon operation of the low voltage switch and delayed termination of the porch light after cessation of operation of said signal.

2. In an electrical circuit of the class described: a source of power; fixed circuit means connected to said source of power and including illumination means; second circuit means connected to said source of power and including audible signal means, said signal means and said illumination means being initially energized simultaneously from said source of power; and third circuit means including a delay acting temperature responsive switch having a controllable heat source and arelay means initiating the energization of said illumination means and maintaining its energization after said signal means is deenergized; said temperature responsive switch deenergizing said relay means and said illumination means in response to the heat source after a fixed delay.

3. In a household electrical circuit of the class described: a source of potential including connection means; a lighting circuit including a series control switch energized by said connection means; a doorbell circuit including a momentary series switch energized by said connection means; a Warp switch including resistance heating means adjacent thereto and having normally closed contacts in series circuit therewith; a relay in series circuit with said contacts and in turn including a plurality of contacts; circuit means including a first of said relay contacts energizing said relay and heater from said connection means upon operation of said momentary switch, and a second of said relay contacts shorting said series control switch; and further circuit means including a third of said relay contacts continuously maintaining the circuit means energized until said normally closed contacts open.

4. In a household electrical circuit of, the class described: a source of electric potential including connection means; a lighting circuit energized from said connection means and including a control switch; a doorbell circuit energized from said conection means and including a momentary switch; a bimetal Warp switch having a resistive heating element adjacent thereto and said switch having normally closed contacts; a relay including a plurality of contact means; series circuit means including the relay, the warp switch heating element, first normally closed relay contact means, and the momentary switch energized from said connection means upon closing said momentary switch; and additional circuit means including second of said relay contact means shorting said control switch to energize said lighting circuit and third of said relay contact means. energizing said series circuit until said heater causes said normally closed switch to open.

References Cited in the file of this patent UNITED STATES PATENTS 1,826,477 Olpp Oct. 6, 1931 2,313,560 Levine Mar. 9, 1943 2,472,741 Berninger et al. June 7, 1949 2,637,801 Kelley et a1. May 5, 1953 

